From 49870534bae0199c1282ec2424670450eb854afe Mon Sep 17 00:00:00 2001
From: Joergen Ibsen <ji@ibse.dk>
Date: Thu, 3 Feb 2022 09:29:14 +0100
Subject: [PATCH] Update CMake list file

Minimum required CMake version is now 3.16.
---
 CMakeLists.txt | 47 ++++++++++++++++++++++++++++++++---------------
 1 file changed, 32 insertions(+), 15 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 10d5ede..910286f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,34 +1,51 @@
-cmake_minimum_required(VERSION 3.0)
+cmake_minimum_required(VERSION 3.16)
 
 project(tinf C)
 
+include(CheckCCompilerFlag)
 include(CTest)
 
 # Check if tinf is the top-level project (standalone), or a subproject
-set(tinf_standalone FALSE)
-get_directory_property(tinf_parent_directory PARENT_DIRECTORY)
-if(tinf_parent_directory STREQUAL "")
-  set(tinf_standalone TRUE)
+set(_tinf_standalone FALSE)
+if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
+  set(_tinf_standalone TRUE)
 endif()
-unset(tinf_parent_directory)
 
 # TINF_BUILD_TESTING controls if tinf adds testing support
 #
 # When built standalone, it defaults to the value of BUILD_TESTING if set.
 # An optional prefix for the test names can be set with TINF_TEST_PREFIX.
-set(tinf_testing_default ON)
-if(tinf_standalone)
+set(_tinf_testing_default ON)
+if(_tinf_standalone)
   if(DEFINED BUILD_TESTING)
-    set(tinf_testing_default ${BUILD_TESTING})
+    set(_tinf_testing_default ${BUILD_TESTING})
   endif()
 else()
-  set(tinf_testing_default OFF)
+  set(_tinf_testing_default OFF)
 endif()
-option(TINF_BUILD_TESTING "Add testing support" ${tinf_testing_default})
-unset(tinf_testing_default)
+option(TINF_BUILD_TESTING "Add testing support" ${_tinf_testing_default})
+unset(_tinf_testing_default)
 
 mark_as_advanced(TINF_TEST_PREFIX)
 
+# Take a list of compiler flags and add those which the compiler accepts to
+# the COMPILE_OPTIONS directory property
+function(add_valid_c_compile_options)
+  foreach(flag IN LISTS ARGN)
+    string(REGEX REPLACE "[^a-zA-Z0-9]+" "_" flag_var "CFLAG_${flag}")
+    check_c_compiler_flag("${flag}" ${flag_var})
+    if(${flag_var})
+      add_compile_options("${flag}")
+    endif()
+  endforeach()
+endfunction()
+
+if(MSVC)
+  add_valid_c_compile_options(/W3)
+else()
+  add_valid_c_compile_options(-Wall -Wextra -pedantic)
+endif()
+
 #
 # tinf
 #
@@ -40,13 +57,13 @@ add_library(tinf
   src/tinfzlib.c
   src/tinf.h
 )
-target_include_directories(tinf PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/src>)
+target_include_directories(tinf PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_LIST_DIR}/src>)
 
 #
 # tgunzip
 #
 add_executable(tgunzip examples/tgunzip/tgunzip.c)
-target_link_libraries(tgunzip tinf)
+target_link_libraries(tgunzip PRIVATE tinf)
 if(MSVC)
   target_compile_definitions(tgunzip PRIVATE _CRT_SECURE_NO_WARNINGS)
 endif()
@@ -56,7 +73,7 @@ endif()
 #
 if(TINF_BUILD_TESTING)
   add_executable(test_tinf test/test_tinf.c)
-  target_link_libraries(test_tinf tinf)
+  target_link_libraries(test_tinf PRIVATE tinf)
   if(MSVC)
     target_compile_definitions(test_tinf PRIVATE _CRT_SECURE_NO_WARNINGS)
   endif()